ST. PETERSBURG, Fla. – A day after Jason Castro suffered a bruised left knee when a ball was fouled off his knee, manager Bo Porter started Carlos Corporan behind the plate and used Castro as the team’s designated hitter Saturday for the third game of a four-game series against the Rays at Tropicana Field.

“It got it right where the VMO (vastus medialis) muscle, right where that attaches to the knee cap,” Castro said. “It’s kind of a bad spot. The only thing it really bothers me is to squat, so hitting and everything seems like it should be fine. I’m DH-ing today so it shouldn’t be a problem.”

Barring any setbacks, Corporan will start at catcher and Castro will be off Sunday as Chris Carter returns to the DH position.

“He’s fine,” Porter said of Castro. “He could catch, but I think that, again, you take advantage of being in the American League and having the DH and being able to keep his bat in the lineup. It also allows Corporan to catch back-to-back days.

“That’s something he hasn’t been able to do. His body is fresh. With the off-day on Sunday I just looked at the time of it. Castro can DH today, take tomorrow off and he gets two days off. Corporan gets to catch back-to-back days and then get a day off. I think it keeps everyone fresh.”

Castro is optimistic that he’ll be fine when he returns behind the plate Tuesday.

“That should probably hopefully do the trick,” Castro said. “Usually with stuff like this as long as you’re getting treatment it should be fine in a couple of days.”